Kim Younghun, Lee Jeongjin, Yi Jongheop
Department of Chemical Engineering, Kwangwoon University, Seoul 139-701, Korea.
J Nanosci Nanotechnol. 2008 Oct;8(10):5090-3. doi: 10.1166/jnn.2008.1004.
To measure the thickness of SAMs, ellipsometry using a p-polarized laser beam is commonly used, which provides indirect information on the entire surface. Herein, a direct method for estimating the thickness of multilayered thiolated-Au films using atomic force microscopy (AFM) oxidation is described. When a bias voltage is applied to thiolated-Au films, the sulfur-gold bond is readily cleaved via a desorption procedure, and the nano-explosion through electron tunneling occurs at the nano-contact between the probe tip and surface. A multi-step uncovered layer is obtained, which can be used to estimate the thickness of each layer (organic and gold). This procedure is referred to as "electronic punch" of AFM, and is applicable to thiolated-Au films.
为了测量自组装单分子膜（SAMs）的厚度，通常使用采用p偏振激光束的椭偏仪，它能提供关于整个表面的间接信息。在此，描述了一种使用原子力显微镜（AFM）氧化来估算多层硫醇化金膜厚度的直接方法。当向硫醇化金膜施加偏置电压时，硫 - 金键会通过解吸过程轻易断裂，并且在探针尖端与表面之间的纳米接触处会发生通过电子隧穿的纳米爆炸。由此获得一个多步骤的未覆盖层，可用于估算每层（有机层和金层）的厚度。此过程被称为AFM的“电子打孔”，适用于硫醇化金膜。
